Internal-combustion engine.



#3 WITNESSES: INVENTOR 1 M 554154 No. 870,720. PATENTED NOV. 12,1907. A.J. FRITH. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 17, 1905.

8 SHEETS-SHEET 1.

'. ATTORNEY PATENTED NOV. 12', 1907.

A. J. FRITH. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 17, 1905.

3 SHEETS-SHEET min WITNESSES: MZQW .AT'TORNEY N0. 8'ZO,720. PATENTEDNOV. 12, 1907. A. J. FRITH.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 17, 1906.

a SHEETS-SHEET s.

WITNESSES: INVENTOR @a@@ A yym ATTORN EY ARTHUR J. FRITH, OF NEW YORK,N. Y.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented Nov. 12, 1907.

Applioation filed April 17. 1905- Serial No. 255,861.

To all .whom it may concern:

Be it known that I, ARTHUR J. Farm, a citizen of the United States ofAmerica, and resident of the city of New York, State of New York, haveinvented certain newand useful Improvements in Internal-CombustionEngines, of which the following is a specification.

. My invention relates to internal combustion engines in which oil, gasor other fuel is caused to burn in a closed cylinder and by-.its actionagainst a movable piston converts heat energy into work.

The object of my invention is to produce an engine 1 of this class whichshall be simple and effective in its construction and operation andespecially one in which the energy wasted in the escape of gases andthrough water cooling shall be materially reduced.

My invention consists in providing means for compressingacharge andraising its temperature by means of stored heat, burning the same,converting part of its energy into work, and then abstracting andstoring some of its heat, and finally converting more of its ener'gyinto work as hereinafter described and pointed out charge containing airis received into the larger cylin- .pressure.

der, compressed therein, passed-through the'regeneratorinto the smallercylinder in a compressed and heated at some point in the regeneratorsomewhat nearer the condition where it is caused to burn, allowed toexpand, then passed back through the regenerator into the largercylinder where it still in thcr expands and is then exhaustedat arelatively ion l 2'. perature and In the drawings accompanying andforming part of this specification Figure 1 is a side view of an engineembodying my invention. Fig. 2 its a plan of the same.

.3 is a cross-section through the cylinders and regenerator'on line a-aof Fig. 4. Fig. "4 is a section on line bb of. Fig. 3. Fig. 5 is a sideview bf the pump and governor, Fig. 6 a section on line 0-0 of Fig. 5,Fig.

7 is a power' diagram, and Fig. 8 is a diagram showing thecombinedvolumes of the cylinders and regenerator in the drawings andspecification.

tor 4 which communicates with the cylinder 2 through the port 5 and'withthe cylinder 3 through the port 6.

The regenerator may be made of any form and material which is capable ofpermitting the gases to pass I through it and of absorbing or storing upheat, and of withstanding high temperatures.'

The cylinder 3 is provided with an inlet valve 7 and an exhaust valve 8and both of the cylinders are providedwith water jackets 9. Theregenerator 4 may be insulated in any appropriate manner as by thelinings 1'7. made of appropriate refractory, insulating material, or byother means.

A piston 10 operates-in the cylinder 2- and is connected by theconnecting rod I1 to the crank pin 12 of the crank shaft 13. Thepiston-l4 operates in the cylinder 3 and is connected by the connectingrod 15 to the crank pin 16. The crank pin 12 is located in advance ofthe crank pin 16 an appropriate amount to give the proper relativemovement to the two pistons 10 and 14. In the engine herein illustratedthis angle of advance is about 105 degrees.-

The exhaust valve 8 is operated by the tappet '18 mounted on the rod 19which engages the crank pin 20.. The said crank pin 20 is secured to thearm 21 which arm is securedto the pin 22, mounted in the gear wheel 23.

The rod 19 passes through a guide 24 which is pivotallyattachedto thecylinder. The gear wheel 23 engages a gear 25 on the crank shaft 13, thegear 25 being halfthe diameter of the former. The gear wheel' 23 alsohas secured to it a belt ,pulley 26 for the-purpose of operating thegovernor.

Fuel in the form of oil or gas is admitted preferably port 5 leadinginto the cylinder 2, than the port 6 of the cylinder 3 as at 27 throughthe pipe 28. The pipe cylinder 29 which, when gas is employed, may bewater jacketed, in which'operates the piston 30. The piston 30 isoperated by the rod 31, one end of which engages the crank pin 22 in thegear 23. Thepipe 28 leads from an appropriate outlet valve and an inletvalve 32 is connected with any convenient supply of gas or other fuel.The cylinder 29 is opened at both ends, the piston-30 operating in oneend as described, while the piston 33 forms an adjustable closure ormovable end for the other end of the cylinder.

Attached to the piston 33 outside of the cylinder is a cross bar 34which is provided with rods 35 passing through the lugs 36'. These rodshave nuts on their ends and springs mounted on them between said nutsand the lugs 36 which tend to keep the cross bar 34 against said lugs.37 is an eccentric or cam mounted on the shaft 38 and adapted to bearagainst the cross adapted to be connected by means of a belt with thebelt wheel 26 on the gear 23. During the outward stroke of the piston'30 the springs on the rods will force the piston'33 inwardly until thecross bar 34 banks against the end of the cylinder. The outward movementof the piston 30 will thendraw in a charge of fuel through the inletvalve 32, the amount of the charge taken in at each outwardstrokeof'the' piston being constant.

During the return or delivery stroke of the piston the inlet valve 32closes and the piston 33"will move outward until its motion is arrestedby the eccentric 37 when the fuel will be forced through the outletvalve into the delivery pipe 28, and into the regenerator 4. Thustheposition of the piston 33 at the end of the delivery stroke of piston 30will be controlled by the governor balls 44, that is, by the speed ofthe engine, and thus the amount of fuel delivered by eachstroke of thepump piston 30 will be controlled by the engine speed.- I I Inb'r'der tokeep the temperature of the air, during its compression, as low aspossible and to approximate as nearly as possible to isothermalcompression, I provide means for saturating the air with moisture beforecompression and before heating the compressed charge by passing itthrough the regenerator prior to ignition.

The addition of moisture to the air during compression to keep thetemperature down, has been found to be.

impracticable heretofore, because. it retards'or interferes with theburning of the gases, but by means of passing the low temperaturecompressed charge'through the regenerator after its compression has beensubstantially completed its temperature is raised to a point Where thepresence of moisture will not interfere with effective burning. By meansof this novel arrange-' ment, that is adding moisture to the air beforeor during compression and raising its temperature after compression andthen igniting it, I am enabled to obtain,

the benefits of substantial isothermal compression with.- outinterfering with effective burning. At the same time an. additionaladvantage is obtained in working the regenerator through a wider rangeoftemperatures,

for it is obvious that if the temperature of thelcomend of this chamberI provide a bed of baffles 50 in front of an open screen 51 throughwhich air is admitted and I provide a jet 52 which is adapted to beconnected with a water supply and to direct a jet of water against andupon the baffles 50, the purpose of this construction being to saturatethe air with moisture and by a 'sort of filtering or separating processto clean it from extraneous grit and dust. At t'hetop of the regeneratorI place a plug 53 which may be removed to allow the escape 'of'gaseswhen fuel is burned the regenerator to heat it preparatory to starting.54 is a valve which controls the communication with a pipe 55 leadingfrom a supply of fuel which is admitted to the regenerator to heat thesame preparatory to starting. An electric or other suitable igniter 56is placed in the cylinder 2 and may be operated in the usual manner toignite the charge when the heat of theregenerator is insufl'icient forthe purpose.

The operation of the engine herein described is what is known as afour-cycle and is as iollows:-Assuming that the engine is running undernormal conditions and that the regenerator is at a high temperature andstarting at a point when the gases of combustion have been practicallyall expelled by the inward movement of the piston 14, the succeedingoutward movement of the piston 14 will draw in a charge. This charge maybe of air, a combustible mixture of fuel and air, or a non-combustiblemixture of .fuel and air. The next succeeding, or inward, stroke of thepiston 14 will compress this charge and force it through the hotregenerator 4 into the cylinder 2, a space being formed therein by theadvance movement of its piston. In case the compressed charge is of-airor of a non-combustible mixture of fuel and air, a charge of; fuel willbe. introduced into the regenerator during the compression of the chargein the cylinder 3 and preferably after the piston 10 has neared the endof its inward stroke, and when .the combined volume of cylinders isapproaching its minimum, that is between positions 8 and 11 in Fig. 8.The compressed and heated mixturetons a greater amount of work will bedeveloped in the smaller cylind erduring the first expansion of thegases on account of the advance movement of the smaller piston 10 whilethe larger piston 14 is at and near the end of its stroke, as will beclearly seen by reference to the diagramFig. 8. While the fuelis firstbeing swept into the high temperature cylinder 2 it will beginto burnslowly on account of the great excess of fuel. At-some time however,before an excess of air is reached the right chemical mixture will beobtained for rapid and explosive combustion. Atfa certain time during orafter the combustion, the piston 14 in the low temperature cylinder willbegin its outward movement during which the gases of combustion willreturn through the regenerator into said cylinder giving up a portion oftheir heat to the regenerator and expanding from the same high pressureas exists in the high temperature cylinder, but at much lowertemperature to the point of exhaust. Inthis way the temperatureand'pressure of the exhaust gases and consequently the quantity of heatlost will be much less than that of the I best gas engine practice as Iunderstand it. During I the succeeding stroke of the piston 14 the gasesof co1nder and the low temperature of the large cylinder the percentageof loss of heat to the cooling water is greatly reduced.

high pressure oi maximum compression and the difii culties inherentthereto. The-danger of too early an explosion is. avoided because thefuel flows into the high temperature cylinder in advance of the deliveryof the charge containing air and the mixture at the point of burning istoo rich to readily ignite or rapidly burn before the point of maximumcompression.

Iii the diagram, Fig. 8 the curved line AB reprevertical lines 1, 2, 3,4,' etc. are 15 degrees apart. The

length of these lines included between the two curves A.B and 'GHrepresents the total volum-efor the particular position of the cranksindicated bythe pd sition oithe lines on the diagram. Thehightemperature piston is at the inner end of its stroke on line 6 while thelow temperature piston reaches the end of its corresponding stroke 105degrees later, that is on line 13. The point of maximum compression isabout on line 12 that isto say, 15 degrees before the low temperaturecylinder is at the end of its stroke. Fuel may be introduced at anypoint between position and 11 without danger of being forced into thelow temperature cylinder.

' The regenerator having been preheated as-fbefore described, the enginemay be started by hand, by compressed air or by an explosive chargeespecially introduced for the purpose or in any other Well-known manner.I In Fig. 7 I have drawn an ideal diagram in full lines designated by'J,representing appr oximately the power diagram of the engine hereindescribed. Upon this diagram I have superimposed in dotted lines asecond diagram designated by K representing an ordinary gas engine,cycle calling for the same expenditure of heat. The increased pressuresrepresented'in diagram] over those of the diagram K, are due to thepreheating of the charge and a greater compression before ignition andthe greater inclination of the line of expansions Ir-M .is due to thefall of pressure resulting from the absorption of heat by theregeneratoras well as the expansion of the gases. v

The dotted extension OP indicates the compression line which would occurprovided the gases were not preheated in the regenerator. This greatercompression could not be used in the ordinary gas engine without dangerof pre-ignition but may be used in my engine, because the air and fuelare kept separate durindicate the increased power and efficiency to beob tained by the use of my invention.

Having thus described my invention What I claim is:

1. In an internal combustion engine, the combination with a cylinder anda combustion chamber, of a regenerator in communication with saidcylinder and said combustion chamber, means for admitting a charge tosaid cylinder, a piston in said cylinder, a piston in said combustionchamber. means connecting said pistons for causing them to so move thatthe charge taken into said cylinder shall be compressed therein andpassed in its compressed state through said regenei'ator into saidcombustion chamber, expand in said combustion chamber against the pistontherein and then be substantially all expelled from said combustionchamber through said regenerator into said cylinder and expand in saidcylinder prior to its exhaust therefrom.

.2. In an internal combustion, engine, the combination with a pair ofcylinders of unequal size, each provided with a movable working piston,and the smaller constituting a combustion chamber, of a regeneratorconnecting said cylinders, an air inlet and an exhaust valve in saidlarger cylinder, and means for imparting relative movements to saidworking pistons such that the charge of air taken in shall reachsubstantially its state of maximum compression prior to its passagethrough the regenerator'into the smaller cylinder from which it shall bereturned through the regenerator and reach substantially its state ofmaximum expansion in the large cylinder prior to its exhaust therefrom.v

3. In an internal combustion engine, the combination with a pair ofcylinders, each provided with a movable piston, and a regeneratorconnecting said cylinders, of means for introducing fuel and ignitingit, means for operating the pistons to compress air in one of saidcylinders, force it through the regenerator into the other cylinderduring combustion and causing the gases of combustion to return throughthe regenerator to the first named cylinder and expand therein.

4. In an internal combustion engine, the combination with a pair ofcylinders of unequal size having their working "ends connected by aregenerator, a piston in said smaller cylinder, of means for forcing acompressed charge from the larger cylinder through the regenerator intothe I smaller cylinder after its substantially maximum compression andduring combustion, and back through the regenerator into the largercylinder after combustion and partial expansion and permitting it toexpand in said larger cylinder.

5. In an internal combustion engine, the combination of a pair ofcylinders having pistons adapted to work therein, one of said cylindersconstituting a combustion chamber, of a regenerator in continuously opencommunication with and connecting the working ends of said cylinders,means for admitting fuel and air, and connections between said pistonscausing the volume included between said pistons to periodicallyincrease and decrease and to cause substantially all of the gases ofcombustion to be expelled from said combustion chamber through saidregenerator into said other cylinder during the time when the combinedvolume of both cylinders increases to its maximum.

6. In an internal combustion engine, the combination with a cylinder, ofa regenerator in communication with said cylinder on one side and acombustion chambenon the other side, means for admitting air to saidcylinder, compressing it therein and forcing it in its compressed statethrough 'said'regenerator into said combustion chamber, means forintroducing fuel and igniting it, and means for expelling the gases fromthe combustion chamber after ignitionto compel them to return throughsaid regenerator and expand in said cylinder.

7. In an internal combustion engine,. the combination with a pair ofcylinders, each provided with a movable working piston. one of saidcylinders constituting the compression cylinder and the other thecombustion chamber, of means for supplying moisture to the charge earlyin the compression, a regenerator connecting said cylinders, and meansfor operating said pistons to force the compressed ing'compression. Therelative areas of these diagrams charge through the regenerator into thecombustion cham loo ber allowing the gases to partially expand in saidcombustion chamber, return through said regenerator and further expandin said compression cylinder. e

8. In an internal combustion engine, the combination with two cylinderseach provided with a piston and in communication with each other througha regenerator, of means for admitting a charge containing air into oneof said cylinders,-means for operating the piston to compress thecharge, therein and pass it through the regenerator into said othercylinder for combustion, and means for controlling the relativemovements of the pistons in said cyl-- inders so that the maximumdisplacement of the last named or combustion cylinder shall be less thanthe original-volume of said charge.

9. In an internal combustion engine, the combination with a pair ofcylinders connected by a regenerator and provided with working pistonsof unequal displacements, the cylinder having the piston of largerdisplacement being provided with inlet and exhaust valves andconstituting the compression cylinder and the other constituting the'combnstion cylinder, cranks connected with said pistons so related thatthe charge taken in, compressed and passed through the regenerator intothe combustion chamber shall be expelled from said combustion chamberthrough said regenerator into said compression cylinder while saidproducts of combustion are expanding to their maximum volumef 10. In aninternal combustion engine, the combination with a cylinder havlng amovable piston therein and a regenerator connected therewith, of meansfor introducing a compressed charge through said regenerator into saidcylinder the original volume of which charge exceeds the maximumdisplacement ofsaid piston, and means for allowing said charge to expandagainst a second working piston while it is being expelled from saidcylinder back through said regenerator.

Intestimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

- ARTHUR J. FRITH.

Witnesses: Y

' Elisha 0. NEWKRANTZ,

Gno. E. HARDY.

